IMMUNOHISTOCHEMICAL DEMONSTRATION OF NEURON-SPECIFIC ENOLASE AND MICROTUBULE-ASSOCIATED PROTEIN-2 IN REACTIVE ASTROCYTES AFTER INJURY IN THE ADULT FOREBRAIN

Transformation of normal resting astrocytes to reactive astrocytes in the adult brain after injury has been well documented. Using double im munofluorescent labeling methods, we report that astrocytes in both th e ischemically damaged and the retrogradely/anterogradely degenerating forebrain nuclei express not only the glial cell markers glial fibril lary acidic protein and vimentin, but also the neuronal markers neuron -specific enolase and microtubule-associated protein 2. Since these ne uronal markers are expressed in glial precursor cells, these results s uggest that one of the characteristic responses of astrocytes in the a dult brain after injury may be re-expression of fetal trait(s) of earl y differentiating glial cells/neurons.